The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 08, 1994
Filed:
Mar. 11, 1992
Applicant:
Inventors:
Kurt Hauenstein, Unterendingen, CH;
Carl W Mayer, Riehen, CH;
Assignee:
Ciba-Geigy Corporation, Ardsley, NY (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
C07D / ; C07D / ; C07D / ; C07D / ;
U.S. Cl.
CPC ...
540-1 ; 423179 ; 423508 ; 423511 ; 549-4 ; 549 31 ;
Abstract
A process for the preparation of peri-dichalcogeno polycyclic aromatic compounds by preparing in a first step, in an amidic solvent, an alkali metal sulfide, selenide or telluride which, in a second step, is reacted with a peri-halogeno aromatic compound, which process comprises reacting in said first step an alkali metal base with elemental sulfur, selenium or tellurium at elevated temperature.